In a small bowl, toss the bonito flakes with the soy sauce until barely moistened.
Rinse the radish sprouts under cold water, shaking off excess moisture. Trim and discard the roots. If you’re using alfalfa sprouts instead, rinse and shake dry; no trimming is necessary.
In a clean, dry skillet, roast the sesame seeds over medium-high heat for 30–40 seconds until they begin to color slightly or a few pop. Shake the pan to keep the seeds in motion. Transfer the roasted seeds to a cutting board and mince them (as you would parsley) just to crack the seeds and release their aroma. Set the cracked seeds aside.
Each roll will use one eighth of the fish flakes, a few stalks of the radish sprouts (or a small clump of alfalfa sprouts), and a sprinkling of sesame seeds.
© 1985 Elizabeth Andoh. All rights reserved.